/*
    * Copyright 2013 smartics, Kronseder & Reiner GmbH
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *     http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package de.smartics.properties.admin.resources.representation.html.share;
  
  import static de.smartics.resteasy.hypermedia.relations.Relations.HOME;
  import static de.smartics.resteasy.hypermedia.relations.Relations.SELF;
  import static de.smartics.resteasy.hypermedia.relations.Relations.UP;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.net.URI;
  import java.security.Principal;
  import java.util.ArrayList;
  import java.util.List;
  
  import javax.ws.rs.core.UriBuilder;
  
  import org.apache.commons.lang.StringUtils;
  
  import de.smartics.html5.jatl.Html;
  import de.smartics.html5.jatl.HtmlFactory;
  import de.smartics.html5.jatl.HtmlResourceContext;
  import de.smartics.properties.admin.resources.controller.ApiResource;
  import de.smartics.properties.admin.resources.representation.share.AbstractRepresentationRenderer;
  import de.smartics.resteasy.hypermedia.renderer.LinkDescriptor;
  import de.smartics.resteasy.hypermedia.resources.Resources;
  
  /**
   * Base implementation for HTML documents.
   *
   * @param <T> the type of the resource the renderer is rendering representations
   *          for.
   */
  public abstract class AbstractHtmlRepresentationRenderer<T> extends
      AbstractRepresentationRenderer<T>
  {
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    // --- members --------------------------------------------------------------
  
    /**
     * The context information to render the representation.
     */
    protected final HtmlResourceContext htmlContext;
  
    /**
     * The factory to access output properties.
     */
    protected final HtmlFactory factory;
  
    /**
     * The HTML instance to create HTML documents.
     */
    protected final Html html;
  
    /**
     * Helper to localize application specific resources.
     */
    protected final HtmlPathHelper pathHelper;
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    /**
     * Default constructor using a stream.
     *
     * @param htmlContext the context information to render the representation.
     * @param entityStream the stream to write to.
     */
    protected AbstractHtmlRepresentationRenderer(
        final HtmlResourceContext htmlContext, final OutputStream entityStream)
    {
      super(htmlContext.getContext(), htmlContext.getFactory().getCharset()
          .displayName(), entityStream, "getAsHtml");
  
      this.htmlContext = htmlContext;
      this.factory = htmlContext.getFactory();
      this.html = factory.create(entityStream);
      this.pathHelper = new HtmlPathHelper(htmlContext.getContext().getUriInfo());
    }
  
    // ****************************** Inner Classes *****************************
  
   // ********************************* Methods ********************************
 
   // --- init -----------------------------------------------------------------
 
   // --- get&set --------------------------------------------------------------
 
   // --- business -------------------------------------------------------------
 
   @Override
   protected final void httpBody()
   {
     html.declaration();
     html.html();
 
     htmlHead();
     htmlBody();
 
     html.end();
   }
 
   private void htmlHead()
   {
     html.head();
     html.title().text(getTitle()).end();
     html.meta().attr("charset", factory.getCharset().toString()).end();
 
     final String bootstrapCssUrl = pathHelper.bootstrap("css/bootstrap.css");
     html.link().rel("stylesheet").type("text/css").href(bootstrapCssUrl)
         .media("screen").end();
 
     final String cssUrl = pathHelper.css("properties.css");
     html.link().rel("stylesheet").type("text/css").href(cssUrl).media("screen")
         .end();
 
     renderApplicationStateHtmlHead();
 
     html.end();
   }
 
   private void renderApplicationStateHtmlHead()
   {
     final Resources discovery = htmlContext.getContext().getDiscovery();
     for (final LinkDescriptor link : discovery.links())
     {
       final String rel = link.getRel();
       final String href = link.getHref();
 
       html.link().rel(rel);
 
       final String type = link.getType();
       if (StringUtils.isNotBlank(type))
       {
         html.type(type);
       }
       html.href(href);
 
       html.end();
     }
   }
 
   /**
    * Returns the title to the page.
    *
    * @return the title to the page.
    */
   protected abstract String getTitle();
 
   /**
    * Renders the subtitle within the page body.
    *
    * @param subTitle the optional sub title to render.
    */
   protected void renderPageTitle(final String subTitle)
   {
     html.div().classAttr("page-header");
 
     html.h1().text(getTitle());
     if (StringUtils.isNotBlank(subTitle))
     {
       html.text(" ").small().text(subTitle).end();
     }
     html.end();
 
     html.end();
   }
 
   private void htmlBody()
   {
     html.body();
     html.script().src(pathHelper.jquery("jquery.js")).end();
     html.script().src(pathHelper.bootstrap("js/bootstrap.js")).end();
 
     html.div().id("wrap");
     controls();
     breadcrumbs();
     html.div().classAttr("container");
     bodyContents();
     html.end();
     html.end();
 
     footer();
     html.end();
   }
 
   private void controls()
   {
     html.div().classAttr("pull-right");
     html.div().classAttr("btn-group");
 
     renderLogout();
 
     html.end();
     html.end();
   }
 
   private void renderLogout()
   {
     final UriBuilder builder =
         htmlContext.getContext().getUriInfo().getBaseUriBuilder();
     final URI uri = builder.path(ApiResource.class, "logout").build();
     final String logoutUrl = uri.toString();
     html.form().classAttr("form-inline").method("POST").action(logoutUrl);
 
     html.button().type("submit").id("logout")
         .classAttr("btn btn-mini btn-default");
     final String user = calcUser();
     html.text("logout " + user).end();
 
     html.end();
   }
 
   private String calcUser()
   {
     final Principal principal =
         htmlContext.getContext().getRequest().getUserPrincipal();
     if (principal != null)
     {
       return principal.getName();
     }
     else
     {
       return "";
     }
   }
 
   /**
    * Returns the breadcrumbs.
    *
    * @return the list of breadcrumb links.
    */
   protected abstract List<LinkDescriptor> breadcrumbLinks();
 
   private void breadcrumbs()
   {
     final List<LinkDescriptor> breadcrumbs = breadcrumbLinks();
     if (breadcrumbs.isEmpty())
     {
       return;
     }
 
     final int size = breadcrumbs.size();
     if (size == 0)
     {
       return;
     }
 
     html.start("nav").ul().classAttr("breadcrumb");
     final List<String> ups = new ArrayList<String>();
     for (int i = 0; i < size - 1; i++)
     {
       final LinkDescriptor link = breadcrumbs.get(i);
       if (i > 0)
       {
         ups.add(UP);
       }
       else
       {
         link.addRels(HOME);
       }
       link.addRels(ups);
       render(link);
     }
     final LinkDescriptor link = breadcrumbs.get(size - 1);
     if (size == 1)
     {
       link.addRels(HOME);
     }
     link.addRels(SELF);
     render(link, true);
 
     html.end().end();
   }
 
   private void render(final LinkDescriptor link)
   {
     render(link, false);
   }
 
   private void render(final LinkDescriptor link, final boolean last)
   {
     final String label = link.getShortLabel();
     if (StringUtils.isNotBlank(label))
     {
       html.li().shortLink(link);
       if (!last)
       {
         html.span().classAttr("divider").text("/").end();
       }
 
       html.end();
     }
   }
 
   /**
    * The contents to write to the HTML body.
    */
   protected abstract void bodyContents();
 
   private void footer()
   {
     html.div().id("footer");
     html.div().classAttr("container");
     html.p().classAttr("muted credit");
     html.text("powered by ");
     html.a().href("http://www.smartics.eu/smartics-properties")
         .text("smartics-properties").end();
     html.end();
     html.end();
   }
 
   @Override
   protected final void close()
   {
     html.done();
     try
     {
       html.getWriter().flush();
     }
     catch (final IOException e)
     {
       // Ignore
     }
   }
 
   // --- object basics --------------------------------------------------------
 
 }